JP4530607B2 - Manufacturing method of fluid processing apparatus with built-in honeycomb structure - Google Patents

Abstract

The present invention is directed to a method of producing a container such as a catalytic converter for holding a fragile substrate in a cylindrical housing (4) with a shock absorbent member (3) wrapped around the substrate (2), with an appropriate holding force determined on the basis of frictional force between the shock absorbent member (3) and the one with the smaller coefficient of friction out of the substrate (2) and the cylindrical housing (4). The method comprises the steps of (1) inserting the substrate (2) with the shock absorbent member (3) wrapped around the substrate (2), into the cylindrical housing (4) loosely, (2) applying an axial load to the substrate (2) so as to move the substrate (2) along a longitudinal axis of the cylindrical housing (4) by a predetermined distance, monitoring the axial load applied to the substrate (2), and (3) reducing a diameter of at least a part of the cylindrical housing (4) with the substrate (2) held therein along the longitudinal axis of the cylindrical housing (4), with the shock absorbent member (3) being compressed, to such an extent that the axial load equals a predetermined value. <IMAGE>

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a fluid treatment apparatus that holds a honeycomb structure in a metallic cylindrical member via a buffer member, and for example, a catalyst carrier of the honeycomb structure is interposed in the cylindrical member via a buffer mat. The present invention relates to a production method suitable as a production method of a catalytic converter to be held.
[0002]
[Prior art]
Modern automobiles are equipped with catalytic converters and diesel particulate filters (hereinafter referred to as “DP filters”). The manufacturing method is to provide a sealing function on the outer periphery of a fragile ceramic catalyst carrier (or filter). A general method is to wind a ceramic buffer mat as the buffer member, and press-fit the buffer mat into a cylindrical member (casing) while compressing the buffer mat.
[0003]
For example, in Japanese Patent Laid-Open No. 2001-355438, the outer diameter of the catalyst carrier is measured when a catalyst carrier having a holding material attached to the outer periphery is press-fitted into a holding cylinder, and the holding member has an inner diameter suitable for the measured value. A method of manufacturing a catalytic converter in which a catalyst carrier having a holding member mounted on a cylinder is press-fitted has been proposed. There has also been proposed a method of measuring the outer diameter of the holding material mounted on the outer periphery of the catalyst carrier and press-fitting the catalyst carrier with the holding material mounted on a holding cylinder having an inner diameter suitable for the measured value. Furthermore, it has been proposed to measure the outer diameter of the holding material in a state where a predetermined pressure is applied. In this publication, it is proposed that materials for a large number of holding cylinders having different inner diameters are prepared in advance, and a material having an appropriate inner diameter is selected from them.
[0004]
On the other hand, a method called sizing or calibrating is also proposed in which after the catalyst carrier and the mat are gently inserted into the cylindrical member, the diameter of the cylindrical member is reduced to a diameter at which the cushioning member mat becomes the optimum compression amount. For example, it is disclosed in JP-A-64-60711, JP-A-8-42333, JP-A-9-170424, JP-A-9-234377, US Pat. No. 5,329,698, US Pat. Yes.
[0005]
For example, in Japanese Patent Application Laid-Open No. 9-234377, in the conventional Japanese Patent Application Laid-Open No. 2-268834, the central portion of the tubular body (cone-integrated casing) 23 is radially reduced in diameter to form a compression part b, and a support mat Although the catalytic converter which compresses 22 and supports the ceramic honeycomb body 21 in the casing is disclosed, the honeycomb body 21 is in the direction of the cones 8a and 8b which are not reduced in diameter from the end of the compression portion b in the central portion. Since the problem is that the gap 9 between the outer periphery and the inner periphery of the casing 23 is large, it has been proposed to reduce the diameter over the entire length of the casing.
[0006]
[Problems to be solved by the invention]
In the above-described press-fitting method, generally, the gap between the outer diameter of the catalyst carrier and the inner diameter of the cylindrical member is set based on the packing density (referred to as GBD value) of the buffer mat serving as the buffer member. This GBD value is the weight per unit area of the buffer mat / the size of the filling gap, and a surface pressure (unit: Pascal) is generated according to the packing density of the buffer mat, and the catalyst carrier is held by this surface pressure. However, the surface pressure is naturally adjusted to a value that does not exceed the strength of the catalyst carrier, and to a value that can be held so that it does not move in the cylindrical member against the catalyst carrier to which vibration or exhaust gas pressure is applied. Must. For this purpose, the buffer mat must be pressed in with a GBD value within the design range, and this GBD value must be maintained during the product life cycle.
[0007]
However, in the above-described method using press-fitting, an error in the outer diameter of the catalyst carrier, an error in the inner diameter of the cylindrical member, and an error in the weight per unit area of the buffer mat interposed between them are inevitably produced in the manufacturing process. Are superimposed on each other, which causes an error in the GBD value. Therefore, finding the optimum combination of each member for minimizing the error of the GBD value cannot be a realistic solution for mass production. Further, the GBD value itself depends on the characteristics of the buffer mat and individual differences, and depends on the measured value on the plane, and does not represent the measured value in a state of being tightly wound around the catalyst carrier. For this reason, it is desired that the catalyst carrier is appropriately accommodated in the cylindrical member without depending on the GBD value as in the prior art.
[0008]
On the other hand, in the sizing method, it is contemplated that the outer diameter of the catalyst carrier and the inner diameter of the cylindrical member are measured in advance, the appropriate compression amount of the buffer mat is obtained, and the diameter is reduced by this compression amount. In this method, it is difficult to finally determine whether or not the compression amount of the buffer mat is optimal. This is because when reducing the diameter of a metal cylindrical member, it is necessary to reduce the diameter in advance (so-called overshoot) smaller than the target diameter in consideration of the spring back of the cylindrical member. . For this reason, there exists a possibility that an excessive compressive force may be provided. Further, since a change in the plate thickness is unavoidable during the diameter reduction processing of the cylindrical member, it is more difficult to set a true inner diameter (inner wall surface position), that is, an accurate diameter reduction amount.
[0009]
As a method for solving the problem caused by the above-mentioned overshoot, in the above-mentioned specification of US Pat. No. 5,755,025, the outer diameter of the catalyst carrier is measured in advance, and the compression mat compression amount is taken into consideration. The optimum outer diameter of the range is calculated, and the cylindrical member is expanded to several kinds of diameters over the entire length based on the calculated outer diameter. Thereafter, the catalyst carrier is used in the selected cylindrical member using a jig similar to the press-fitting method. And we are going to press fit the buffer mat. However, since no consideration is given to the error in the weight per unit area of the buffer mat, it is inevitable that an error occurs in the surface pressure applied to the catalyst carrier.
[0010]
Here, the holding force required to hold the catalyst carrier at a predetermined position in the cylindrical member will be described. The holding force in the radial direction of the cylindrical member is applied to the outer surface of the catalyst carrier and the inner surface of the cylindrical member. It is the compression restoring force of the buffer mat that works in the direction perpendicular to the direction. On the other hand, for example, an axial force is generated by vibration or exhaust gas pressure in the catalyst carrier and the buffer mat with respect to the cylindrical member fixed to the exhaust device of the automobile, for example. A holding force in the (longitudinal direction) is necessary, and this is where the frictional force between the buffer mat and the catalyst carrier, and the frictional force between the buffer mat and the cylindrical member contribute.
[0011]
The frictional force between the buffer mat and the catalyst carrier, and the frictional force between the buffer mat and the cylindrical member, respectively, determine the coefficient of static friction between the outer surface of the catalyst carrier and the buffer mat, and the compression restoring force of the buffer mat. The product multiplied by (surface pressure) and the product obtained by multiplying the static friction coefficient between the inner surface of the cylindrical member and the buffer mat by the compression restoring force (surface pressure) of the buffer mat. At this time, as the holding force in the axial direction (longitudinal direction), the frictional force between the member having a lower static friction coefficient and the buffer mat is dominant. Therefore, the necessary frictional force is clarified for the catalyst carrier and the cylindrical member whose static friction coefficient is known, and in order to ensure this, it is necessary to increase the surface pressure against the buffer mat, but the catalyst carrier is fragile. In this case, in order to avoid an excessive radial load, it is necessary to set the axial holding force within the limit of the surface pressure against the buffer mat.
[0012]
Thus, the surface pressure with respect to the buffer mat is set based on the static friction coefficient of the lower member of the static friction coefficient of the outer surface of the catalyst carrier and the static friction coefficient of the inner surface of the cylindrical member, and the cylinder pressure is determined according to the surface pressure. The diameter of the member may be reduced. However, in the conventional method, the management based on the above-mentioned GBD value is general, that is, the estimation management based on the substitute value is performed. For this reason, not only the estimation factor is superimposed and the error is unavoidable, but as a result, the holding force due to the frictional force between the buffer mat and the catalyst carrier and the friction between the buffer mat and the cylindrical member are reduced. The holding force by force is confused, and the dimensional relationship of each part is set.
[0013]
After all, the most appropriate control parameter when holding the catalyst carrier in the tubular member via the buffer mat is the surface pressure applied to the honeycomb structure (catalyst carrier or filter) via the buffer member (buffer mat). It is. Therefore, if the surface pressure can be directly detected and the diameter of the cylindrical member can be reduced based on the detection result, the diameter of the cylindrical member can be reduced with good accuracy by sizing.
[0014]
However, it is very difficult to measure the above surface pressure itself, particularly in a state where the buffer mat and the catalyst carrier are accommodated in the cylindrical member and the surface pressure is generated by the reaction force of the buffer mat. It is necessary to insert the measuring device into the cylindrical member for measurement and take out the device after the measurement. However, this is very difficult and not practical. On the other hand, it is conceivable to measure the strain or the like of the cylindrical member and use it as a substitute value of the surface pressure. However, the measurement accuracy cannot be declined, and an accurate surface pressure value cannot be grasped.
[0015]
Therefore, the present invention monitors the holding force when holding the honeycomb structure in the metal cylindrical member via the buffer member, reduces the diameter of the cylindrical member, and places the honeycomb structure in the cylindrical member. It is an object of the present invention to provide a method for manufacturing a fluid treatment apparatus that can be appropriately held.
[0016]
[Means for Solving the Problems]
In order to solve the above-described problems, a method for manufacturing a fluid processing apparatus with a built-in honeycomb structure according to the present invention includes a honeycomb structure in which a honeycomb structure is held in a metal cylindrical member via a buffer member as described in claim 1. In the manufacturing method of the fluid processing apparatus with a built-in structure, the buffer member is housed in the cylindrical member in a state of being mounted around the honeycomb structure and held at a predetermined position, and then at least a portion of the buffer member is housed. When reducing the diameter of a predetermined range in the axial direction of the tubular member, when applying an axial load to the honeycomb structure and moving the honeycomb structure in the axial direction with respect to the cylindrical member The axial load value is monitored, and the axial load value is Target axial load The diameter reduction of the cylindrical member is performed until reaching the value. In addition, when the buffer member and the honeycomb structure are accommodated in the tubular member, they may be accommodated gently, but may be accommodated in a state close to press-fitting in anticipation of several diameter reductions. Good (hereinafter the same). In addition, the predetermined distance is a maximum value of the axial load when the honeycomb structure is moved in the axial direction in a state where an optimal compressive load is applied to the honeycomb structure (this is referred to as “extraction load”). It is good to set it to a value that is equal to or greater than the axial movement distance at the time.
[0019]
Claims 2 As described in the above, in the method for manufacturing a honeycomb structure built-in fluid processing apparatus in which the honeycomb structure is held in the metal cylindrical member via the buffer member, the buffer member is mounted around the honeycomb structure. The first reduction of the cylindrical member when the first diameter reduction processing is performed with respect to a predetermined range in the axial direction of the cylindrical member that is accommodated in the cylindrical member and at least a portion that accommodates the buffer member. Measures the first load when the honeycomb structure is moved by a predetermined distance in the axial direction with respect to the tubular member by measuring the diameter amount and applying an axial load to the honeycomb structure. And measuring a second diameter reduction amount of the cylindrical member when the second diameter reduction process is performed on the axially predetermined range of the cylindrical member, and applying an axial load to the honeycomb structure. To give the honeycomb structure the tubular shape Measure the second load when moved a predetermined distance in the axial direction relative to the material, based on the correlation between the first and second reduced diameter amount and the first and second axial load, Estimating a target diameter reduction amount of the cylindrical member when the honeycomb structure is held in the cylindrical member with a predetermined target holding force, and further reducing the diameter of the cylindrical member until the target diameter reduction amount is reached. It is good also as processing.
[0020]
Furthermore, the claim 2 In the manufacturing method described in claim 3 As described above, the two measurements may be performed by moving the honeycomb structure by a predetermined distance with respect to the tubular member in the same axial direction. Alternatively, the claim 2 In the manufacturing method described in claim 4 As described above, the two measurements may be performed by moving the honeycomb structure by a predetermined distance with respect to the cylindrical member in opposite axial directions.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a method for manufacturing a fluid treatment apparatus that holds a honeycomb structure in a metal cylindrical member via a buffer member, and as a specific embodiment thereof, a method for manufacturing a catalytic converter for automobiles will be described with reference to the drawings. To do. In addition to the catalytic converter, the fluid treatment device to be manufactured of the present invention includes, for example, a DP filter device and a purification filter. Further, a reformer for a fuel cell described in JP-A-2002-50383 and 68709 is also available. Is included.
[0022]
The cylindrical member is also called an outer cylinder, a housing, or a casing. In the case of a catalytic converter, the honeycomb structure corresponds to a catalyst carrier, and the buffer member corresponds to a buffer mat for holding the catalyst carrier. In the case of the DP filter device, the honeycomb structure corresponds to a filter, and the buffer member corresponds to a buffer mat for the DP filter. The catalyst carrier or DP filter constituting the honeycomb structure is generally formed in a columnar shape or a cylindrical shape, and has a circular cross section, but is not limited thereto, an elliptical cross section, an oval cross section, a surface having a plurality of curvatures. It is good also as non-circular cross sections, such as a cross-section which combined and polygonal cross-section. Further, the flow path (cell) cross section of the catalyst carrier or the DP filter is not limited to the honeycomb (hexagonal shape), and may be any square shape.
[0023]
In the present embodiment, as shown in the center portion of FIG. 1, the buffer mat 3 constituting the buffer member of the present invention is wound around the outer periphery of the catalyst carrier 2 and is fixed by a combustible tape or the like as necessary. The In this case, although not shown, it is preferable to use a general winding method in which convex portions and concave portions are formed at both ends of the buffer mat 3 and these are fitted to each other. Further, since there is also a buffer member formed in a cylindrical shape in advance, in this case, the buffer member is mounted around the catalyst carrier 2 simply by housing the catalyst carrier 2 in the cylindrical buffer member. .
[0024]
The catalyst carrier 2 is composed of a ceramic honeycomb structure, and the walls between the cells (flow paths) are formed thin, which is more fragile than the conventional product. The buffer mat 3 is composed of an alumina mat that hardly expands due to heat in the present embodiment, but may be a thermal expansion type vermiculite buffer mat or a buffer mat that combines them. Further, an inorganic fiber mat not impregnated with a binder may be used. Since the surface pressure varies depending on the presence and content of the binder, it is necessary to take this into consideration when setting the surface pressure. Or you may use the wire mesh etc. which knitted the metal fine wire, and may use it in combination with a ceramic mat. Further, they may be combined with a metal annular retainer, a wire mesh seal ring, or the like.
[0025]
Next, the catalyst carrier 2 on which the buffer mat 3 is mounted as described above is gently accommodated in the cylindrical member 4 (or accommodated in a state close to press-fitting in anticipation of several diameter reductions), After being held at a predetermined position by the sizing device SM shown in FIG. 1, the predetermined range of the cylindrical member 4 is reduced in diameter. In this embodiment, as shown in FIG. 1, a catalyst carrier holding device HM is disposed vertically through the base 10, and the collet chuck of the sizing device SM is disposed on the base 10 so as to surround it. It is installed. In the holding device HM, a cradle 11 and a cylinder 12 are fixed in a hole drilled in the base 10, and a shaft 13 driven by the cylinder 12 is slidably supported through the cradle 11. Yes. Further, a shaft 14 having a distal end surface facing the distal end surface of the shaft 13 is supported by a cylinder 15 so as to be driven in the vertical direction. A load cell 16 is interposed between the shaft 14 and the cylinder 15 so that the axial load applied to the catalyst carrier by the cylinder 15 via the shaft 14 can be measured. The load cell 16 is electrically connected to the controller 30.
[0026]
On the other hand, in the sizing device SM, a plurality of split molds 21 are supported by an annular frame member 20 having a U-shaped cross section so as to be able to slide on the base 10 in the radial direction (axial direction). A mold (collet) 22 is fixed to the inner diameter side of the split mold 21, and a tapered surface is formed on the outer diameter side (back side) of each split mold 21. A pressing die 23 is disposed so as to accommodate these split dies 21, and a tapered surface that is in sliding contact with the tapered surface of the split die 21 is formed on the inner diameter side. The pressing die 23 may be formed in a cylindrical shape or may be divided so as to abut on each split die 21. The pressing die 23 is fixed to a pressing plate 24, and the pressing plate 24 is supported via a support member 25 so as to be movable up and down. Thus, the pressing plate 24 drives the pressing die 23 in the vertical direction. For example, when the pressing die 23 is driven downward in FIG. 1, the split die 21 is driven in the radial direction (axial direction). ing. The push plate 24 is driven by a hydraulic drive device (not shown), and this hydraulic drive device is controlled by the controller 30.
[0027]
The operation of the sizing device SM configured as described above will be described. First, as shown in FIG. 1, the cylindrical member 4 is placed on the upper surface of the cradle 11. At this time, the shaft 13 is located on the axis of the cylindrical member 4. Next, the catalyst carrier 2 on which the buffer mat 3 is mounted is gently accommodated in the cylindrical member 4 and placed on the tip surface of the shaft 13. Further, the shaft 14 is driven downward by the cylinder 15, and the catalyst carrier 2 is sandwiched between the front end surface of the shaft 14 and the front end surface of the shaft 13. Then, the push plate 24 is driven downward in FIG. 1 by a hydraulic drive device (not shown). Thereby, the pressing die 23 is driven downward in FIG. 1, and the split die 21 is driven in the radial direction (axial direction). As a result, as shown in FIG. 2, the barrel 22 (intermediate portion) of the cylindrical member 4 and the buffer mat 3 are compressed and reduced in diameter by the mold 22. The amount of diameter reduction at this time is accurately controlled by the control of the hydraulic drive device by the controller 30. Thus, the catalyst carrier 2 is held in a stable state in the cylindrical member 4.
[0028]
As described above, the hydraulic drive device (not shown) of the sizing device SM is controlled by the controller 30, and is particularly configured to be able to perform an arbitrary amount of sizing by NC control, and can be finely controlled. . Further, when the diameter is reduced, for example, if the workpiece is rotated sequentially (at any time) and indexing control (index control) is performed, the diameter can be reduced more uniformly over the entire circumference. Note that the drive and control medium of the sizing device SM is not limited to hydraulic pressure, and any drive method such as mechanical, electric or pneumatic is used for the drive and control type, and control is performed using CNC control. Is preferred.
[0029]
Next, a specific example of a diameter reduction process for reducing the diameter of the body of the tubular member 4 together with the buffer mat 3 by a diameter reduction process a plurality of times (in this embodiment, twice) using the sizing device SM having the above-described configuration. Will be described with reference to FIGS. FIG. 3 shows that the buffer mat 3 is accommodated in the cylindrical member 4 with the catalyst carrier 2 mounted, and the buffer mat 3 is appropriately compressed by reducing the diameter of a predetermined range in the axial direction of the cylindrical member 4. The relationship with respect to the axial movement distance (stroke) of the catalyst carrier 2 when an axial load is applied to the catalyst carrier 2 with the catalyst carrier 2 held is shown. By the way, the frictional force between the buffer mat 3 and the catalyst carrier 2 and the frictional force between the buffer mat 3 and the cylindrical member 4 respectively have a static friction coefficient between the outer surface of the catalyst carrier 2 and the buffer mat 3. The product obtained by multiplying the compression restoring force (surface pressure) of the buffer mat 3 and the product obtained by multiplying the compression friction force (surface pressure) of the buffer mat 3 by the static friction coefficient between the inner surface of the tubular member 4 and the buffer mat 3. expressed. At this time, as the holding force in the axial direction (longitudinal direction), the frictional force between the member having the lower static friction coefficient and the buffer mat 3 is dominant. Therefore, the necessary frictional force becomes clear with respect to the catalyst carrier 2 and the cylindrical member 4 whose static friction coefficients are known.
[0030]
In FIG. 3, the axial load becomes a maximum value (Fp, which is referred to as “pull load”) as the axial movement distance of the catalyst carrier 2 increases, and then rapidly decreases and then gradually decreases. Show. The axial load at this time corresponds to the frictional force between the member having the lower static friction coefficient of the catalyst carrier 2 and the cylindrical member 4 and the buffer mat 3, so that the axial load is the extraction load (Fp). The axial movement distance (Sp, for example, 1.5 mm) becomes a stroke at which the maximum frictional force can be obtained. Specifying this axial movement distance (Sp) is not easy to be entangled with various conditions, but if it is moved at least by an axial movement distance (Sx) greater than this value (Sp), the maximum frictional force, that is, the removal force The load (Fp) can be detected. Accordingly, for example, 2 mm (> Sp) is selected as the axial movement distance (Sx), and the value when the axial load is maximized in the state where the optimum compressive load is applied to the buffer mat 3 (extraction) Load (Fp)), and the amount of compression of the buffer mat 3 (the amount of diameter reduction of the cylindrical member 4) is adjusted with the detection result as the target axial load (Ft), the catalyst carrier 2 and the cylindrical member 4 A desired frictional force can be secured between the member having the lower static friction coefficient and the buffer mat 3.
[0031]
The dynamic friction coefficient in a substantially stable region at a position larger than the axial movement distance (Sx) (a position on the right side of Sx in FIG. 3) may be monitored. That is, whether to manage sizing by focusing on the peak value (maximum static friction coefficient) or sizing management by focusing on the maximum dynamic friction coefficient (dynamic state) as described above depends on the individual design or manufacturing. It may be selected according to the background. In any case, of the frictional force between the buffer mat and the catalyst carrier and the frictional force between the buffer mat and the cylindrical member, only the relative movement in which the frictional force starts to move first is monitored. In this respect, the ease of manufacturing according to the present embodiment is clear.
[0032]
On the other hand, FIG. 4 shows the relationship between the reduced diameter (horizontal axis) of the cylindrical member 4 that applies a compressive load to the buffer mat 3 and the axial load (vertical axis) applied to the catalyst carrier 2. A solid line at the center of the maximum load characteristic indicated by a two-dot chain line and the minimum load characteristic indicated by a broken line is a correlation line of the present embodiment, and represents a substantially straight line. In FIG. 4, the target axial load (Ft) set based on the characteristics of FIG. 3 as described above and the compressive load on the cushioning mat 3 being optimal and the target axial load (Ft) are applied. The relationship with the target diameter reduction amount (St) of the cylindrical member 4 to be obtained can be specified as follows.
[0033]
First, in the first diameter reduction processing, the buffer mat 3 is gently housed in the tubular member 4 in a state where the buffer mat 3 is mounted around the catalyst carrier 2, and the shaft of the tubular member 4 in the portion for housing the buffer mat 3 is used. And measuring the first diameter reduction amount (S1) of the cylindrical member 4 when the first diameter reduction processing is performed for a predetermined range in the direction, and applying an axial load to the catalyst support 2 to thereby provide the catalyst support A first load (F1) is measured when 2 is moved in the axial direction with respect to the cylindrical member 4 by a predetermined distance (for example, 2 mm in the axial movement distance (Sx) in FIG. 3). The first diameter reduction amount (S1) at point a in FIG. 4 is the distance from the inner surface (point 0 in FIG. 4) of the cylindrical member 4 before diameter reduction, and the radial movement distance of the split mold 21 As a result, it can be obtained based on the hydraulic pressure of a hydraulic drive device (not shown) for driving the push plate 24.
[0034]
Subsequently, the second diameter reduction processing is performed, and the second diameter reduction amount (S2) of the cylindrical member 4 when the second diameter reduction processing is performed with respect to a predetermined axial range of the cylindrical member 4. Is measured, and an axial load is applied to the catalyst carrier 2 to place the catalyst carrier 2 in the axial direction with respect to the cylindrical member 4 (for example, in the same direction as the moving direction during the first diameter reduction process). The second load (F2) when moved (for example, 2 mm) is measured. The second diameter reduction amount (S2) at point b in FIG. 4 is also the distance from the inner side surface (point 0 in FIG. 4) of the cylindrical member 4 before the diameter reduction, and the radial movement distance of the split mold 21; As a result, it can obtain | require based on the oil_pressure | hydraulic of the hydraulic drive apparatus (not shown) for a drive of the push plate 24. FIG. Therefore, the amount of movement from point a to point b in FIG. 4 is (S2-S1).
[0035]
Then, based on the correlation between the first and second diameter reduction amounts (S1, S2) and the first and second axial loads (F1, F2), the catalyst carrier 2 is subjected to a predetermined target holding force (corresponding to this). The diameter reduction amount (St) of the cylindrical member 4 when it is held in the cylindrical member 4 at a target axial load to be Ft) is estimated. That is, as shown in FIG. 4, the cylindrical member 4 is reduced in diameter until a diameter reduction amount (St) corresponding to a preset target axial load (Ft) is reached. Note that the target value of the inner diameter of the cylindrical member 4 (indicated by Rt in FIG. 4) is set, and when the cylindrical member 4 is reduced in diameter and reaches the first and second inner diameters (R1, R2). Based on the correlation with the first and second axial loads (F1, F2), a target value (Rt) of the inner diameter of the cylindrical member 4 is set, and the cylindrical member until this target value (Rt) is reached. You may comprise so that 4 diameter reduction processing may be performed. The inner diameter of the cylindrical member 4 can be obtained by subtracting the moving distance of the mold 22 (split mold 21) from a predetermined distance between the initial position of the mold 22 and the axis of the catalyst carrier 2.
[0036]
The two measurements are performed by moving the catalyst carrier 2 with respect to the cylindrical member 4 in the same axial direction by a predetermined distance (2 mm), and moving the catalyst carrier 2 in the axial direction for a total of 4 mm. Therefore, assuming this total moving distance (4 mm) in advance, as an initial position when the catalyst carrier 2 is arranged in the cylindrical member 4, a position retracted by the total moving distance (4 mm) in the direction opposite to the moving direction. Or after the diameter reduction processing, the total movement distance may be retracted in the direction opposite to the movement direction.
[0037]
Alternatively, the two measurements may be performed by moving the catalyst carrier 2 with respect to the cylindrical member 4 in the opposite axial directions by a predetermined distance (2 mm). That is, if the same distance (2 mm) is moved in the opposite axial direction for each measurement, the movement distance is canceled by the two measurements and the catalyst carrier 2 is returned to the initial position of the cylindrical member 4. It will be. However, since the measurement error is smaller when the buffer mat 3 is measured in a state where a force in a certain direction is applied, it is preferable to move the buffer mat 3 a plurality of times in the same direction as in the present embodiment.
[0038]
In addition, after the above two measurements, the catalyst carrier 2 may be moved at the point c in FIG. 4 to measure the axial load. Usually, however, it is predicted from the measurement results of the two points so far. Therefore, three measurements are not necessary in the mass production process. Similarly, when it is known that the correlation line returns to a straight line as shown in FIG. 4, it is hardly meaningful to measure at three or more points up to point c in FIG. To further explain this, strictly speaking, the estimated correlation line is between two upper and lower curves including the straight line shown in FIG. Therefore, in order to obtain the optimum point c on the line, in addition to the points a and b, measurement is performed at one point, and a quadratic curve is obtained by the least square method based on the measurement results of these three points. What is necessary is just to obtain | require c point on the curve, and a more precise measurement is attained by this. However, since the above accuracy is not required for mass production of catalytic converters and the like targeted by the present invention, the productivity is prioritized and the linear estimation shown in FIG. It is supposed to be replaced with a straight line approximate to the curve. If the axial movement of the catalyst carrier 2 and the measurement of the axial load on the catalyst carrier 2 can be continuously performed during the diameter reduction processing, the load measurement may be performed while moving the catalyst carrier 2.
[0039]
As described above, in order to ensure a desired frictional force between the catalyst carrier 2 and the cylindrical member 4 having a lower coefficient of static friction and the buffer mat 3, the surface pressure on the buffer mat 3 is increased. However, when the catalyst support 2 is weak, in order to avoid an excessive radial load, the axial direction is within the limit of the surface pressure against the buffer mat 3 as shown in FIG. It is necessary to set so as to be able to secure a sufficient holding force. At this time, in consideration of variations in surface pressure due to errors in the outer diameter of the catalyst carrier 2 and changes over time, or surface pressure that can suppress axial movement of the catalyst carrier 2 due to various accelerations during use (at this time Ideally, the compressive force of the buffer mat 3 should be as strong as possible and uniformly applied in both the circumferential direction and the axial direction. If the compression force is set excessively to cope with this, the catalyst carrier 2 may be damaged, so the compression force cannot be greater than a predetermined value (the pressure at which the catalyst carrier 2 is damaged (isostatic strength) ) Is β).
[0040]
In particular, due to the recent demand for improved exhaust purification performance, the catalyst carrier 2 is required to have a thinner wall, and is significantly weaker (that is, lowering β) than the conventional catalyst carrier, and the allowable range for setting the holding force. (It can be expressed by (β−α) as a damage margin against the surface pressure) is further narrowed. Further, since the exhaust gas temperature (the temperature of the exhaust gas introduced into the catalytic converter) increases (becomes about 900 ° C.), it is necessary to combine an alumina mat having high heat resistance as the buffer mat 3. However, since the alumina mat is thermally non-expandable, it is difficult to follow the deformation of the heat-expandable metal cylindrical member. The compression density of the buffer mat 3 must be set larger than the method. Therefore, when using the conventional clamshell (commonly called mid-alignment) method or press-fitting method, as shown by the range A in FIG. 5, a wide surface pressure variation range (the diameter reduction range is Sa1 to Sa2. ), Which means that there is almost no safety margin (margin) for the required minimum surface pressure value α and isostatic strength β. Therefore, it is very difficult to load a thin-walled catalyst carrier or filter while maintaining an appropriate surface pressure by the conventional clamshell method or press-fitting method.
[0041]
In order to cope with the above problem, after the catalyst carrier 2 and the buffer mat 3 are gently inserted into the cylindrical member 4, the cylindrical member 4 is reduced in diameter by a certain amount to compress the buffer mat 3. In this method, as shown in the range B in FIG. 5, it is still necessary to assume a considerably wide surface pressure variation range (the diameter reduction range is Sb1 to Sb2). It is not easy to apply to a wall catalyst support or filter.
[0042]
On the other hand, according to the diameter reduction process in the present embodiment, as shown by a range C in FIG. 5, the surface pressure variation range can be reduced to about 30% of the conventional range A (the diameter reduction amount). Is a range from Sc1 to Sc2). As a result, a large margin of D can be secured for the necessary minimum surface pressure value α. Thereby, even a thin-walled catalyst carrier or filter can be sized without problems. In addition, as the margin D increases, the surface pressure variation range C can be shifted downward, thereby increasing the margin for the isostatic strength β. Furthermore, since the surface pressure itself can be set at a small level, work and management are facilitated, the buffer mat 3 can be set thin, and the gap can be reduced, contributing to weight reduction and cost reduction. It will be. Thus, according to the present embodiment, even the fragile catalyst carrier 2 is always held in the cylindrical member 4 via the buffer mat 3 with a stable accuracy without being destroyed. Can do.
[0043]
Further, in the present embodiment, as described above, the necking process by spinning is performed on both ends of the cylindrical member 4 in which the catalyst carrier 2 and the buffer mat 3 are accommodated as follows. First, as shown in FIG. 6, the trunk portion (reduced diameter portion) 4a of the cylindrical member 4 is sandwiched by a clamping device (not shown) for a spinning device (not shown), and cannot be rotated and moved in the axial direction. Fix impossible. Then, a spinning process is performed on one end portion of the cylindrical member 4 by a plurality of spinning rollers SP revolving around the outer periphery of the one end portion of the cylindrical member 4 along a circular locus having the same diameter. That is, the spinning rollers SP, which are preferably arranged at equal intervals around the outer periphery of the cylindrical member 4, are brought into close contact with the outer peripheral surface of the cylindrical member 4 and revolved, and the shaft is rotated in the radial direction while reducing the revolution locus. Spinning is performed by driving in the direction (right direction in FIG. 6).
[0044]
Thus, as shown on the right side of FIG. 6, a spinning process is performed (polymerized) including a stepped part formed after the diameter reduction process of the body part 4a of the cylindrical member 4, and through this polymerization process part, the spinning process is performed. Spinning is performed so that the diameter of the cylindrical member 4 is continuously reduced from the body portion 4a, and a tapered portion 4b and a neck portion (bottleneck portion) 4c are formed at one end portion of the cylindrical member 4. As a result, a continuous surface is formed through the polymerization processing portion without leaving a non-processing portion between the body portion 4a and the taper portion 4b.
[0045]
Further, the cylindrical member 4 processed as described above is arranged by being inverted 180 degrees, and the other end portion of the cylindrical member 4 is also necked by the spinning roller SP in the same manner as described above, and the cylindrical portion 4a A tapered portion 4d and a neck portion 4e are formed around an axis inclined with respect to the central axis. Thus, a catalytic converter is formed as shown in FIG. In this case, a plurality of traces parallel to the outer surface of the body portion 4a are formed on the cylindrical member 4 by the diameter reduction process, and a plurality of striations are formed on the outer surfaces of the tapered parts 4b and 4d by the spinning process. As shown by a broken line in FIG. 7, both end portions of the trace at the time of diameter reduction disappear when the tapered portions 4b and 4d are formed, and form a shape that intersects the stripe at the time of spinning. The above traces are specific to the construction method using the sizing device SM shown in FIG. 1, and the stripes are specific to spinning processing, but the traces and lines indicating the traces in FIG. It is drawn with emphasis for convenience of explanation, and it is desirable that it is actually thin and not visible if possible.
[0046]
In addition, as described in JP-A-2001-107725, spinning processing may be employed in the diameter reducing process of the body portion of the cylindrical member 4. Further, the number of catalyst carriers 2 is not necessarily one, but two may be arranged in the axial direction to form a tandem type, or three or more may be arranged in series. The diameter may be reduced for each portion corresponding to the honeycomb structure, or may be continuously reduced. And as a final product, it is not restricted to the exhaust system parts of a motor vehicle, The manufacturing method of this invention is applicable to various fluid processing apparatuses, such as the above-mentioned reformer for fuel cells.
[0047]
【The invention's effect】
Since this invention is comprised as mentioned above, there exists an effect as described below. That is, claim 1 In In the method for manufacturing a fluid processing apparatus with a built-in honeycomb structure, an axial load is applied to the honeycomb structure when the predetermined diameter range of the cylindrical member that accommodates at least the buffer member is reduced. The value of the axial load when the honeycomb structure is moved a predetermined distance in the axial direction with respect to the tubular member is monitored, and the value of the axial load is Target axial load Therefore, the cylindrical member can be reduced in diameter with a very good accuracy which is always stable.
[0048]
In particular, since the moving load of the honeycomb structure itself is directly monitored instead of the substitute value, the honeycomb structure can be held with a predetermined target holding force with high accuracy while minimizing the error. Therefore, it is not affected by the outer diameter error of the honeycomb structure, the inner diameter error of the cylindrical member, the error of the buffer member, etc., and without requiring a management index in place of the above GBD value, with high accuracy. The diameter of the cylindrical member can be reduced. Furthermore, since the movement load itself of the honeycomb structure required as a final product can be satisfied, the movement (missing) inspection of the honeycomb structure conventionally required can be omitted, and the manufacturing time can be shortened accordingly. be able to. Thus, the fluid processing apparatus can be easily manufactured in a short time, and can be easily adapted to the mass production process.
[0049]
Claims 2 Thru 4 In the method for manufacturing a fluid processing apparatus with a built-in honeycomb structure according to the above, the cylindrical member when the first diameter reduction process is performed on a predetermined range in the axial direction of the cylindrical member that accommodates at least the buffer member. While measuring the first amount of diameter reduction, applying an axial load to the honeycomb structure to measure the first load when the honeycomb structure is moved a predetermined distance in the axial direction with respect to the tubular member, Subsequently, similarly, the second reduced diameter amount and the second load are measured. Based on the correlation between the first and second reduced diameter amounts and the first and second axial loads, the honeycomb structure Estimating a target diameter reduction amount of the cylindrical member when the body is held in the cylindrical member with a predetermined target holding force, and further reducing the diameter of the cylindrical member until the target diameter reduction amount is reached. Therefore, the diameter of the cylindrical member can be reduced with better accuracy. Further, like the above-described method, the fluid processing apparatus can be easily manufactured in a short time, and can be easily adapted to the mass production process.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a sizing device used in a manufacturing method according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a state where a cylindrical member is reduced in diameter by a sizing device provided for a manufacturing method according to an embodiment of the present invention.
FIG. 3 shows a shaft of a catalyst carrier when an axial load is applied to the catalyst carrier in a state where a predetermined range in the axial direction of the cylindrical member is reduced and the buffer mat is appropriately compressed to hold the catalyst carrier. It is a graph which shows the relationship with respect to a direction moving distance.
FIG. 4 is a graph showing the relationship between the amount of diameter reduction of a cylindrical member that applies a compressive load to the buffer mat and the axial load applied to the catalyst carrier.
FIG. 5 is a graph showing an allowable surface pressure range for an example of a buffer member used in a general catalytic converter.
FIG. 6 is a cross-sectional view showing a state in which necking is performed by a spinning roller in the manufacturing method according to the embodiment of the present invention.
FIG. 7 is a cross-sectional view showing an example of a catalytic converter manufactured by a manufacturing method according to an embodiment of the present invention.
[Explanation of symbols]
2 catalyst carrier, 3 buffer mat, 4 cylindrical member, 4a body,
4b, 4d taper, 4c, 4e neck, 11 cradle,
16 load cells, 21 split molds, 22 molds, 23 press molds,
HM catalyst carrier holding device, SM sizing device, SP spinning roller

Claims (4)

In a manufacturing method of a honeycomb structure built-in fluid processing apparatus in which a honeycomb structure is held in a metal cylindrical member via a buffer member, the buffer member is mounted in the cylindrical member with the buffer member mounted around the honeycomb structure. After the housing and holding at a predetermined position, at the time of reducing the diameter in a predetermined axial range of the cylindrical member at least in the portion where the buffer member is housed, an axial load is applied to the honeycomb structure to provide the honeycomb structure. the value of the axial load when the structure by a predetermined distance in the axial direction with respect to the tubular member monitors, contraction of the tubular member until the value of the axial load reaches the target axial load A manufacturing method of a fluid processing apparatus with a built-in honeycomb structure, characterized by performing diameter processing.   In a manufacturing method of a honeycomb structure built-in fluid processing apparatus in which a honeycomb structure is held in a metal cylindrical member via a buffer member, the buffer member is mounted in the cylindrical member with the buffer member mounted around the honeycomb structure. And measuring a first diameter reduction amount of the cylindrical member when the first diameter reduction processing is performed on a predetermined axial range of the cylindrical member of the cylindrical member at least in a portion of the buffer member. Measuring a first load when an axial load is applied to the honeycomb structure and the honeycomb structure is moved a predetermined distance in the axial direction with respect to the tubular member, and then the tubular member is measured. Measuring the second diameter reduction amount of the tubular member when the second diameter reduction processing is performed on the predetermined range in the axial direction of the honeycomb structure and applying an axial load to the honeycomb structure. Axial structure with respect to the tubular member And measuring the second load when moved to a predetermined distance to the honeycomb structure based on a correlation between the first and second reduced diameter amounts and the first and second axial loads. Estimating a target diameter reduction amount of the cylindrical member when it is held in the cylindrical member with a target holding force, and further reducing the diameter of the cylindrical member until the target diameter reduction amount is reached. A method for manufacturing a honeycomb structure built-in fluid processing apparatus. 3. The honeycomb structure built-in fluid processing apparatus according to claim 2, wherein the two measurements are performed by moving the honeycomb structure by a predetermined distance with respect to the tubular member in the same axial direction. Production method. 3. The honeycomb structure built-in fluid processing apparatus according to claim 2, wherein the two measurements are performed by moving the honeycomb structure by a predetermined distance with respect to the tubular member in opposite axial directions. Manufacturing method.

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